Environmental Issues

WITHOUT TALKING, brainstorm WITHOUT TALKING, brainstorm individually and write down as individually and write down as many many environmental issuesenvironmental issues as as you can think of.you can think of.

1)1)2)2)3)3)4)4)5)5)

6)6)7)7)8)8)9)9)10)10)

PollutionPollution

What is it?What is it?• Harmful substances discharged into the air, soil, or water

• EX: garbage, chemicals, radioactive waste, noise, thermal, light, sewage, pesticides, fertilizers

Why do we care?Why do we care?•Pollution destroys environments, kills species, spreads disease, causes cancer; reproductive and respiratory problems in humans and animals•Air pollution is the main cause of global warming

SolutionsSolutions• Properly dispose of polluting substances • Monitor emission levels to be within acceptable limits• THREE R’s

POLLUTIONPOLLUTION

Ozone DepletionOzone Depletion

Ozone Layer

• Ozone layer absorbs 97% Ozone layer absorbs 97% to 99% of ultraviolet (UV) to 99% of ultraviolet (UV) radiation from the sunradiation from the sun

• 78% nitrogen gas78% nitrogen gas

• 21% oxygen gas21% oxygen gas

• 1% other gases1% other gases

OZONE DEPLETIONOZONE DEPLETION

Ozone Ozone a 3-atom molecule of oxygen (O a 3-atom molecule of oxygen (O33))

This is a completely different compound than This is a completely different compound than the oxygen we breathe (Othe oxygen we breathe (O22). Ozone is actually ). Ozone is actually

a toxic gas when given off at ground level.a toxic gas when given off at ground level.

OZONE DEPLETIONOZONE DEPLETION

Chlorofluorocarbons (CFCs)Chlorofluorocarbons (CFCs)

The major problemThe major problem::

After a chlorine (Cl) atom After a chlorine (Cl) atom removes an oxygen removes an oxygen molecule from Omolecule from O3 3 it is it is able to separate from the able to separate from the lone oxygen atom and lone oxygen atom and combine with another Ocombine with another O3 3

molecule, so the process molecule, so the process continues over and over continues over and over and over again (up to and over again (up to 100 years).100 years).

Chemicals once used in aerosol cans, plastics, and refrigerators that Chemicals once used in aerosol cans, plastics, and refrigerators that are now mostly banned. are now mostly banned. CFCs break up the ozone layer.CFCs break up the ozone layer.

OZONE DEPLETIONOZONE DEPLETION

After breaking down an ozone molecule, the chlorine atom After breaking down an ozone molecule, the chlorine atom frees itself from the oxygen atom to restart the reaction.frees itself from the oxygen atom to restart the reaction.

OZONE DEPLETIONOZONE DEPLETION

Without the ozone layer larger amounts of UV Without the ozone layer larger amounts of UV rays can reach the earth and potentially rays can reach the earth and potentially cause cancer in humans, cause cataracts cause cancer in humans, cause cataracts (damage eye-sight), and affect crop growth.(damage eye-sight), and affect crop growth.

• UV induces skin cancer by UV induces skin cancer by causing mutations in DNA. causing mutations in DNA.

• The United Nations The United Nations Environment Program Environment Program estimates that a sustained 1 estimates that a sustained 1 percent depletion of ozone will percent depletion of ozone will ultimately lead to a 2-3 percent ultimately lead to a 2-3 percent increase in the incidence of increase in the incidence of non-melanoma skin cancer.non-melanoma skin cancer.

OZONE DEPLETIONOZONE DEPLETION

Overexposure to ultraviolet radiation can change the flowering times of some kinds of plants and therefore will affect the animals that depend on them.

Marine organisms living in shallow water experience damaging levels of ultraviolet (UV) radiation. A healthy green sea urchin embryo appears above left. A UV-irradiated green sea urchin embryo (above right) displays an abnormal, extruded gut.

UV radiation also impairs UV radiation also impairs the process of the process of

photosynthesis in plants.photosynthesis in plants.

Since the Montreal Protocol, is the ozone Since the Montreal Protocol, is the ozone layer completely back to normal?layer completely back to normal?

OZONE DEPLETIONOZONE DEPLETION

• The good news is that CFCs have been banned and can no longer damage the ozone layer

• Montreal Protocol treaty including over 200 countries has banned the use of CFCs.

The ozone layer is predicted to make a recovery to what it was in 1980 by 2050

• http://www.epa.gov/ozone/science/movies/forecastearth_3_300.wmv

OZONE DEPLETIONOZONE DEPLETION

Deforestation / Deforestation / Habitat LossHabitat Loss

What is it?What is it?• Natural environments destroyed due to agriculture,

excessive logging, forest fires, industrial and residential development

DEFORESTATIONDEFORESTATION

Why do we care?Why do we care?• Loss of biodiversity• Greatest cause of extinction• Trees act as filters for excess CO2 in the air; less trees

more CO2

• Not sustainable in the long term• New medicines, foods, and products

SolutionsSolutions

• Conserve natural areas• Designate more lands for national/state parks• Sustainable agriculture

19851985

19921992

These NASA photographs, showing the destruction of the Amazon Rain Forest, provide a visual indication of the rate of deforestation that is taking place in Brazil. In many areas, the amount of clear-cut area now exceeds the area of remaining rain forest timber stands. The solid dark green areas show the remaining tropical rain forest canopy. Scientists predict that half of the Amazon Rain Forest will be gone by 2030.

Click the map above to see Amazon deforestation Click the map above to see Amazon deforestation through GoogleMaps.through GoogleMaps.

See these light patches all over?See these light

patches all over?

DEFORESTATIONDEFORESTATION

A Solution you can Take Part in!!

Acid RainAcid Rain

What is it?What is it?• Precipitation becomes acidic due to air pollution

• Burning fossil fuels (emissions from high sulfur coal)

• Sulfur dissolves and mixes with oxygen to become acidic

ACID RAINACID RAIN

ACID RAINACID RAIN

Why do we care?Why do we care?• Damage caused by Acid Rain:

– Forests and soil– Aquatic ecosystems– Materials (building, statues, etc.)– Air Visibility (smog)– Human Health (heart and lung disorders)

ACID RAINACID RAIN

SolutionsSolutions•Burn less high sulfur coal• Develop alternative energies

Human Population Human Population GrowthGrowth

World population didn’t hit 1 Billion until around 1850.

Which parts of the world have the Which parts of the world have the highest rate of population growth?highest rate of population growth?

How many people can the Earth support before How many people can the Earth support before it reaches its carrying capacity?it reaches its carrying capacity?

??HUMAN HUMAN OVERPOPULATIONOVERPOPULATION

Population density per square kilometer

HUMAN HUMAN OVERPOPULATIONOVERPOPULATION

What is it?What is it?• Skyrocketing world population in the last 150 years

• Due to industrial revolution, advances in medicine, food, and technology

HUMAN HUMAN OVERPOPULATIONOVERPOPULATION

Why do we care?Why do we care?

• Population cannot grow indefinitely (carrying capacity)

• Larger population more pollution, scarcity of resources

SolutionsSolutions• Education• Fight poverty• ZPG = Zero Population Growth (Birth Rate = Death Rate)• Family Planning Activity with China, India & Kenya

www.census.gov/main/www/popclock.html

www.BreathingEarth.net

www.pbs.org/wgbh/nova/worldbalance/

Links to Check Out

HUMAN HUMAN OVERPOPULATIONOVERPOPULATION